The inner worker classes of SerialSessionImpl violates the guarded block contract for Object#wait(). Under certain conditions it is possible that a session write starved.
The wait loops of Read- and WriteWorker should be inside the synchronized block! We have some starvations while writing data to or serial session. We found out that in this case the WriteWorker-Thread waits endless for data to write. Because we write data asynchron to the serial session, we assume that a race condition occures. One thread is inside the unguarded WriterWorker#flushWrites() while an other invoke SerialProcessor#flush().
states-> Always invoke wait inside a loop that tests for the condition being waited for. Don't assume that the interrupt was for the particular condition you were waiting for, or that the condition is still true.